| AVS 56th International Symposium & Exhibition | |
| Thin Film | Thursday Sessions |
| Session TF-ThP |
| Session: | Aspects of Thin Films Poster Session |
| Presenter: | J.B. Sorge, University of Alberta, Canada |
| Authors: | J.B. Sorge, University of Alberta, Canada M.J. Brett, NRC National Institute for Nanotechnology, Canada |
| Correspondent: | Click to Email |
In a traditional glancing angle deposition (GLAD) process, the column tilt angle β and film density ρ are both governed by the deposition angle α. It was later discovered that β could be controlled independently from the deposition angle by implementing an appropriately designed phisweep substrate rotation algorithm which reduces anisotropic shadowing1. Ion-assisted deposition has also been demonstrated to alter columnar thin film morphology2 which has proven to be useful in humidity sensing applications3. The influence of the phisweep process on β is inherently limited to producing tilt angles that are less than or equal to that of a traditional GLAD film grown without phisweep. Ion assisted GLAD is a procedure that can increase β above the maximum achievable tilt angle in a standard GLAD deposition and has been utilized in square spiral photonic crystal fabrication4. The work reported here is a fundamental study of SiO2 columnar thin films grown with an ion-beam assisted GLAD process. Our current capabilities in modifying β as a function of α with an ion assisted process will be described. In addition, we report on our efforts to decouple the film density ρ from α; a previously unstudied characteristic of the ion assisted GLAD process. This latter result could enable partial decoupling of α, β and ρ simultaneously and allow access to previously unattainable columnar film morphologies, improving the versatility of the GLAD process. Discussion will focus on the effect of ion assistance on ρ and β as measured by variable angle spectroscopic ellipsometry (VASE) and the influence of different α. The relationship between these parameters, the natural column broadening and effects on the resulting in-plane birefringence will also be discussed.
[1] M. O. Jensen, and M. J. Brett, Appl. Phys. A, 80, 763 (2005)
[2] I. Hodgkinson, and Q.H. Wu, Mod. Phys. Lett. B, 15, 1328 (2001)
[3] M.T. Taschuk, J.B. Sorge, J.J. Steele, and M.J. Brett, IEEE Sensors Journal, 8, 1521 (2008)
[4] J.B. Sorge, M. A. Summers, M. D. Fleischauer, K. Tabunshchyk, A. Kovalenko, and M. J. Brett, Mat. Res. Soc. Sym. Proc., 1014E, 1014-AA07-26 (2007)